RESUMEN
Acute suppurative thyroiditis (AST) is an uncommon condition because thyroid gland is remarkably resistant to infections. In children, anatomic defects such as a left pyriform sinus fistula or a thyroglossal duct remnant predispose to this infection. Once the diagnosis is confirmed by ultrasound or computed tomography, antimicrobial therapy based on the culture and Gram staining must be started. After two or three weeks of treatment, predisposing anatomic defects must be sought cautiously. We report a 13 years old girl presenting with cervical pain and fever. A cervical ultrasound showed an enlarged thyroid lobule with hypoecogenic zones that suggested a supurative collection. Cefotaxime and cloxacillin were started. A needle aspiration of the collection obtained a purulent material. The culture of this material yielded a Streptococcus Pneumoniae. The clinical condition of the patient improved and she was discharged in good conditions. Two months later a contrast esophagus X ray did not show predisposing anatomic defects.